minix/kernel/system/do_irqctl.c
Jorrit Herder c0718054e9 Various fixes and improvements.
- fixed bug that caused IDLE to panic (irq hook inconsistency);
- kprintf() now accepts multiple arguments; moved to utility.c;
- prepare_shutdown() signals system processes with SIGKSTOP;
- phys_fill() renamed to phys_memset(), argument order changed;
- kmemset() removed in favor of phys_kmemset();
- kstrncpy() removed in favor of phys_copy();
- katoi, kstrncmp replaced by normal library procedure again;
- rm_irq_handler() interface changed (simply pass hook pointer);
2005-07-20 15:25:38 +00:00

95 lines
3 KiB
C

/* The system call implemented in this file:
* m_type: SYS_IRQCTL
*
* The parameters for this system call are:
* m5_c1: IRQ_REQUEST (control operation to perform)
* m5_c2: IRQ_VECTOR (irq line that must be controlled)
* m5_i1: IRQ_POLICY (irq policy allows reenabling interrupts)
* m5_l3: IRQ_HOOK_ID (index of irq hook assigned at kernel)
*
* Author:
* Jorrit N. Herder <jnherder@cs.vu.nl>
*/
#include "../system.h"
#if USE_IRQCTL
/*===========================================================================*
* do_irqctl *
*===========================================================================*/
PUBLIC int do_irqctl(m_ptr)
register message *m_ptr; /* pointer to request message */
{
/* Dismember the request message. */
int irq_vec;
int irq_hook_id;
int r = OK;
irq_hook_t *hook_ptr;
/* Hook identifiers start at 1 and end at NR_IRQ_HOOKS. */
irq_hook_id = (unsigned) m_ptr->IRQ_HOOK_ID - 1;
irq_vec = (unsigned) m_ptr->IRQ_VECTOR;
/* See what is requested and take needed actions. */
switch(m_ptr->IRQ_REQUEST) {
/* Enable or disable IRQs. This is straightforward. */
case IRQ_ENABLE:
case IRQ_DISABLE:
if (irq_hook_id >= NR_IRQ_HOOKS ||
irq_hooks[irq_hook_id].proc_nr == NONE) return(EINVAL);
if (irq_hooks[irq_hook_id].proc_nr != m_ptr->m_source) return(EPERM);
if (m_ptr->IRQ_REQUEST == IRQ_ENABLE)
enable_irq(&irq_hooks[irq_hook_id]);
else
disable_irq(&irq_hooks[irq_hook_id]);
break;
/* Control IRQ policies. Set a policy and needed details in the IRQ table.
* This policy is used by a generic function to handle hardware interrupts.
*/
case IRQ_SETPOLICY:
/* Check if IRQ line is acceptable. */
if (irq_vec < 0 || irq_vec >= NR_IRQ_VECTORS) return(EINVAL);
/* Find a free IRQ hook for this mapping. */
hook_ptr = NULL;
for (irq_hook_id=0; irq_hook_id<NR_IRQ_HOOKS; irq_hook_id++) {
if (irq_hooks[irq_hook_id].proc_nr == NONE) {
hook_ptr = &irq_hooks[irq_hook_id]; /* free hook */
break;
}
}
if (hook_ptr == NULL) return(ENOSPC);
/* Only caller can request IRQ mappings. Install handler. */
hook_ptr->proc_nr = m_ptr->m_source; /* process to notify */
hook_ptr->policy = m_ptr->IRQ_POLICY; /* policy for interrupts */
put_irq_handler(hook_ptr, irq_vec, generic_handler);
/* Return index of the IRQ hook in use. */
m_ptr->IRQ_HOOK_ID = irq_hook_id + 1;
break;
case IRQ_RMPOLICY:
if (irq_hook_id >= NR_IRQ_HOOKS ||
irq_hooks[irq_hook_id].proc_nr == NONE) {
return(EINVAL);
} else if (m_ptr->m_source != irq_hooks[irq_hook_id].proc_nr) {
return(EPERM);
}
/* Remove the handler and return. */
rm_irq_handler(&irq_hooks[irq_hook_id]);
break;
default:
r = EINVAL; /* invalid IRQ_REQUEST */
}
return(r);
}
#endif /* USE_IRQCTL */